Calculator



A. E. GOLDFARB 3,127,686

CALCULATOR 3 Sheebs-Shee'fl 1 ADOLPH E. GOLDFARH,

INVENTOR.

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ATTOPNEK April 7, 1964 Filed March 5, 1961 April 7, 1964 A. E. GOLDFARB3,127,686

CALCULATOR Filed March s, 1961 3 sheets-sheet 2 INVENTQR..

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ATTORNEY.

April 7, 1964 A. E. GOLDFARB CALCULATOR 3 Sheets-Sheet I5 Filed March 5,1961 ADOLPH E. GOLDFARB,

INVENTOR.

ATTORNEY.

United States Patent O 3,127,636 CALCULATGR Adolph E. Goldfarb, 7427Varna St., North Hollywood, Calif. Filed Mar. 3, 1961, Ser. No. 93,079 5Claims. (Cl. 35-31) This invention relates to a calculator and moreparticularly to la simplified or instruction type of calculator usefulfor teaching children the fundamentals of arithmetic including theoperation of addition, subtraction, multiplication, and division.

This invention provides a new and improved calculator having arelatively flat base in which a sinuous passageway is defined, thepassageway extending back and forth across the face of the base from oneblind end to another land the base being tiltable and supportable eitherby manual means or by `a foldable support 1therefor in an inclined orvertical position wherein all portions of the passageway `are slopeddownwardly. A manually operable Igate is mounted on the base and isspring-biased into a position intersecting a midway portion of thepassageway so as to block the passageway and is manually operable toselectively remove the gate from the passageway so as to allow apredetermined quantity of rolling members, such as balls, or the like,to be gravitationally biased from 'an upper portion of the passageway toa lower portion thereof.

The balls normally reside in the upper portion of the passageway and arearranged 4in single iile in -the passageway so that the Ilowermost ofthe balls rests against the gate when it is blocking the p-assageway.-When the gate is removed from the passageway, the balls aregravitationally biased to enter the lower portion of the passageway,towards the lowermost blind end thereof.

Stop means are provided and insertable through slits formed in atransparent cover enclosing the passageway, the stop means beingselectively positionable relative to a given problem to be solved toarrest a given amount of balls in the upper portion of the passagewaywhile releasing a given number of balls to roll downwardly towards theblind end in response to removal of the gate from its blocking position.In this manner, simple problems of `arithmetic may be vividlyillustrated and quickly understood and performed by a young child.

For example, in solving an addition problem, la given number of ballsare released through the gate means to he deposited in the lowermostportion of the passageway in addition to a given numbe-r of ballspreviously released thereto, the total being visibly indicated byindicia printed or otherwise 4applied on the transparent cover. Theindicia are unique by being increasingly visible when balls underliethem `and substantially invisible when -tne space in the passagewaybeneath the indicia is unoccupied.

Subtraction is similarly performed whereby a given number of balls of agiven total are released to roll into the lowermost portion of ythepassageway -to obtain the result; multiplication is performed byreleasing a given amount of balls a given number of times into theresult portion of the passageway; and division is performed by releasingan equal amount of balls from a given total of balls into the lowermostportion of the passageway and recording the number of times the givenamount of balls were released to obtain the result.

After obtaining the results, lthe balls in the lowermost portion of thepassageway may be returned to the uppermost portion by reversing thetilt of the calculator base and opening the gate to allow gravitationalrolling of the balls to their original position, after which the gate isreleased for closing the passageway and, when again tilted into itsoriginal position, is ready for operation.

3,127,686 Patented Apr. 7, 1964 It is among the objects of thisinvention to provide a new and improved calculator which is simplifiedin its construction and operation so as to clearly and simply illustratevarious functions of arithmetica'l operations.

An object of this invention is to provide a new and improved calculatorwhich quickly and visibly indicates the results of the variousmathematical operations.

Another object of this invention is to provide a new and improvedcalculator in which the problems are easily and readily fed into theapparatus and the results are progressively and accumulativelyillustrated.

A further object of this invention is to provide a new and improvedcalculator which is easily and practically supported manually in itsoperational position or is optionally supported permanently ornon-permanently on a table or desk or the like by support meanscompactly foldable within the body thereof.

A still further object of this invention is Ato provide a new Vandimproved calculator of the character described which is economical tomanufacture and capable of mass production.

A general object of this invention is to provide a new and improvedcalculator of the character described which overcomes disadvantages ofprior means and methods heretofore intended to accomplish generallysimilar purposes.

These and other objects of this invention will be more apparent from thefollowing drawings, detailed description and -appended claims.

In the dr-awings:

iFIG. l is a -top plan view of lthe calculator of this invention, withparts broken away for great clarity;

FIG. 2 is a perspective view, in elevation, of a removable stop meansembodied in this invention;

FIG. 3 is an enlarged, fragmentary, cross-sectional view as takensubstantially lalong the line 3 3 of iFIG. l;

FIG. 4 is a fragmentary bottom plan view illustrating the underside ofFIG. 43;

FIG. 5 is a cross-sectional view as viewed substantially along the lineS-5 of FlG. 4;

FIG. 6 is a perspective View illustrating a portion of Athe indicatingmeans embodied in this invention in greater detail;

FIG. 7 is an enlarged, fragmentary cross-sectional View as takensubstantially along the line 77 of FIG. l;

FIG. 8 is a cross-sectional View, similar to FIG. 7, illustrating therelationship of the stop means of FIG. 2 to the passageway during usethereof;

FIG. 9 is an enlarged, fragmentary plan view illustrating a portion ofthe passageway of FIG. l, and the relationship of a pair of stop meansthereto;

FiG. 10 is a cross-sectional view, as taken substantially along the line10e-1b of FIG. 9; and

FlG. ll is a side View of the calculator supported in an angularposition.

Referring in detail to the drawings, there is shown by way ofillustration, but not of limitation, a calculator designed andconstructed in accordance with this invention and generally referred toby the numeral 10. The calculator 10 comprises a base 11 having arelatively flat top wall 12 and side walls 13 and a handle 14 extendinglaterally from one of the side walls 13. The walls 12 and 13 and thehandle `1d are preferably formed integrally by casting, molding, or thelike, of a relatively light and rigid material such as plastics or thelike. The top wall 12 is preferably indented as at 16 for accommodatinga panel 17 of transparent material such as plastics, glass, or the like.The panel 17 preferably comprises an unbreakable material such asplastics and is cemented or otherwise secured to the outer face of thewall 12 dened by the indentation 16 for a purpose to be hereinafterdescribed.

A sinuous passageway, generally indicated by the numeral 18, is formedin the Wall 12. The passageway 18 includes a groove 13, preferablyintegrally formed in the face of a top wall 12 and having a pair ofblind ends 21 and 22. The groove 19 is uniform in width and comprises aplurali-ty of lrectilinear portions 23 in convergent and divergentangular relationship to cach other, as best illustrated in FIG. l, andcurved portions 24 connecting the rectilinear portions. The transparentpanel 17 overlies the groove 19 to enclose the passageway 13 providing acontinuous passageway extending from the blind end 21 and extending backand forth to the blind end 22, yet being visible through the panel.

The calculator is easily and readily carried by the use of the handle14. The handle 14 may also be used to manually tilt the base 11 into anangular position illustrated in FIG. 11 or to a vertical position,wherein all rectilinear and curved portions of the passageway 18 aresloped downwardly from horizontal for a purpose to be hereinafterdescribed.

Separate means are provided for optionally permanently ornon-permanently supporting the base 11 in the tilted position. Asupporting means, best illustrated in FIGS. 1 and 11, is preferably ofthe easel type in which a U- shaped bracket 26 is hingedly secured as atits free ends 27 to the side walls 13. The bracket 26 is swingable intoan angular position relative to the base 1.1 into a predeterminedpracticable position determined as by a stop 28. By this means thecalculator 1@ may be supported as on one edge of an end wall 13 and thebight portion 29 of the bracket 26 during the various operations to behereinafter described.

A gate means, generally referred to by the numeral 31, is mounted in thebase 11 for reciprocal movement of a gate member 32 thereof into aposition, illustrated in FIGS. 1, 3 `and 4, interrceptring thepassageway f1.8 for blocking the passageway. The lgate member 32 isselectively positionable by manually operable means to be hereinafterdescribed into open positions, one of which is indicated by the ybrokenlines 32' in FIG. 3, wherein the gate member 32 is clear of thepassageway for opening the passageway.

The gate means 31 includes a slide member 33 movably secured to theunderside of the wall 12 for linear movement in a slideway 34 transverseto an adjacent curved portion 24 midway of the passageway 18. The gatemember 32 is secured to the slide member 33 for linear movementtherewith so that a spring 36 biasing the slide means 33 in a directiontowards the passageway 18 normally biases the gate member 32 into aposition blocking the passageway 18. The gate member 32 includes arelatively thin portion 37 extensible through a slot 38 formed in thewall portion 35 dening the groove 19.

A manually operable actuating member 39 is slidably disposed on theouter surface of the wall 12 as in a slide- Way 41 and has a reducedshank 42 extending through a slot 43 of the wall 12 and into an aperture44 of the slide means 33 for securement thereto as by a fastener. Themember 39 preferably includes a finger-engaging concave surface 46 tofacilitate engagement as by a linger of the operator to slide the member39 in a direction to cornpress the spring 36, thereby sliding the slidemeans 33 and the gate member 32 in a direction to retract the gatemember 32 from the passageway 18 to open the passageway. Upon release ofthe member 39, the slide 33 is biased by the spring 36 to extend thereduced portion 37 of the gate member 32 through the slot 38 to blockthe passageway 18.

The gate member 32 is movable relative to the slide member 33 foropening movement independent of the slide means 33. For this purpose, asecond manually operable actuating member 47, having a concavelingerengaging surface 48, includes a reduced shank portion 49 slidablein a second transverse bore 51 of the slide member 33, the gate member32 being secured to an outer end 52 of the shank for movement therewith.A spring means 53 is interposed between the wall 12 and the underside ofthe finger-engaging portion 47 to normally bias the gate member 32 intoabutment with the slide means 33. In this position, the reduced portion37 of the gate member is biased into the blocking relationship relativeto the passageway 18. The member 47 may be depressed or pushed inwardlyagainst the bias of the spring 53 to extend the gate member 32 to theposition indicated at 32 of FIG. 3 to clear the passageway for openingthereof.

It will now be more clearly understood from the foregoing descriptionthat the gate member 32 is reciprocal in a slot 38 communicating withthe passageway 18 by lateral movement of the slide means 33 to compressthe spring 36 and retract the reduced portion 37 of the gate member 32from the passageway 18 or by a downward or inward movement of theactuating member 47, independently of the slide means 33, to accomplishthe same purpose.

An indicator means is provided to visibly tabulate the number ofactuations of the actuator member 39. The indicating means, generallyreferred to by the numeral 60, includes a disc 61 underlying the wall 12and having a predetermined number of equally and circumferentiallyspaced indicia 62 imprinted on a face 63 adjacent to the underside of`the wall 12 and visible as through a window 64 formed in the wall. Theindicia 62, herein illustrated, indicate numerals consecutively from oneto nine and a zero indicating a zero or a 10. An escapement means 66 ispivotally secured as at 67 to the underside of the wall 12 and isoperatively associated with the disc 61 and the slide means 33 totranslate the linear movement of the slide 33 into an intermittentrotation of the disc 61 so as to progressively rotate the disc 61 andthe numerals thereon in response to each actuation of the slide means 33by the actuating member 39.

The escapement mechanism 66 includes a bell crank 68 pivotably mountedon the underside of the wall 12 as at 67 and having one end 69 securedto the slide means 33 as by a screw 71 extending through a slot 72provided in the end 69 and an offset end 73 underlying the disc 61. Apair of lugs 74 and 76 are alternately engageable with equally spacedpins 77 depending from the disc 61. The lugs are radially spaced fromthe pivot 67 of the bell crank 68 so that when the slide means 33 isbiased into the position to block the passageway 18 with the gate member32, the lug 76 is positioned to intercept the path of movement of thepins like 77 so that the pin 77 most adjacent thereto abuts the lug 76.The disc 61 is rotatable by the force of a torque spring 78 having oneend 79 abutting a pin 81 movable with the disc 61 and another end 82anchored as at lugs 84 secured to the wall 12. The pin 81 is located ona plate 84 secured to a post 86 integral with or secured to the disc 61.An extension 87 of the post 86 extends through a hole S8 of the wall 12for pivotally mounting the disc 61. A manually operable knob 89 issecured to the extension 87 for manual rotation of the post 86 to windthe spring 78.

With the spring 7 8 wound, the disc 61 is biased to rotate and therebybiases a pin 7 to abut against the lug 76 when the slide 33 is in thepassageway-closing position. In this position, the lug 74 is clear ofthe path of the pin 77. When the slide means 33 is actuated to withdrawthe gate member 32 to open the passageway 18, the bell crank 66 ispivoted at 67 to pivot the end 73 into the broken line position 73 ofFIG. 4 to position the lug 74 into the path of the pins 77 and removethe lug 76 from its abutting pin 77. The disc 61 thereby rotates inresponse to the torque of the spring 78 to position the next adjacentpin 77 into abutment with the lug 74 while the pin 77 passes the lug 76.Thereupon, in response to release of the actuator member 46 for bias ofthe spring 36 to return the slide member 33 to the solid line positionof FIG. 4, the bell crank 66 is pivoted to its solid line position ofthe same figure to remove the lug 74 from the pin 77" and swing the lug76 into the path of the oncoming pin 77". The disc 61 may now againrotate under the force of the spring 78 to abut the pin 77" against thelug 76 and position the ensuing numeral (like l) to underlie the window64 to indicate one actuation of the actuating member 39. Subsequentactuation of the actuator 39 again actuates the bell crank 66 to allowprogressive rotation of the disc 61 to reveal the ensuing numeral(numeral 2) signifying the completion of the second actuation of themember 39.

A plurality of equally sized rollable members are disposed in single lein an upper portion 85 (above the midway curved portion 24') of thepassageway 18. The rollable members 80 are preferably relatively heavyand spherical in configuration to minimize friction within thepassageway 18 and are gravitationally biased when the base 11 is tiltedupwardly, as previously described, to roll downwardly in the passageway18 for abutment of the lowermost ball indicated by the numeral 80 withthe reduced portion 37 of the gate member 32 when the gate means is inits closed position. When the gate member is positioned to open thepassageway, the balls 80 and 80' are free to enter a lower portion 90 ofthe passageway 18 and towards the lower blind end 22 of the passageway.

Stop members like the stop member 91, as best illustrated in FIG. 2, areselectively positionable relative to the passageway 18 so as tointercept a selective ball 80 to prevent rolling movement thereof and ofballs 80 which are backed up above the ball. By this means, the balls8i) and 89 which are now positioned between a stop means 91 and the gatemeans 31 are released to enter the lower portion 90 of the passageway inresponse to actuation of the gate means 31 to open the passageway. nthis manner, various problems may be applied to the calculator 1t) toobtain results, as will be hereinafter described.

The stop means 91 includes an enlarged head 92 having a generally Dconguration and a depending relatively thin forked portion 93. Theforked portion 93 is extensible through any of a plurality of slots 94extending through the transparent plate 17. The slots 94 are spaced,relative to the passageway 18, in increments equalling the diameter ofthe rollable members 80 whereby the stop means 91 may be positioned tointercept and block any selected ball 8b for a purpose to be hereinafterdescribed. The forked ends 93 provide cut-outs 96 which clear the balls80, as best seen in FIGS. 8 and l0, so as not to separate the balls whenthe forked ends 93 are inserted through the slots 94.

indicia 97 are provided by printing, engraving, or the like, on theouter surface of the transparent plate 17 and coinciding with the spacesbetween slots 94 for numerically indicating the `number of balls storedin the upper portion 35 of the passageway 18. As best seen in FIG. l,the indicia 97 includes consecutive numbers from l to 100 for visiblyindicating the balls occupying the groove portion 35.

The lower portion 90 of the passageway 18 is similarly identiied bynumerical indicia 98 progressing from the blind end 22 and upwardly tooverlie the groove 18, similarly indicating numerals consecutively froml to 100.

Means are preferably provided for making the numerals of the indicia 97and 98 more prominently visible when a ball like 80 occupies the spacethereunder. For this purpose, the interior of the passageway 13 ispreferably coated with a color, like black, identical to the color usedfor applying the numerals to the exterior of the plate 17, whereas theballs Si) are preferably uncolored and having their metallic finish. Bythis means, when a space under a numeral is unoccupied by a ball Si),the numeral is substantially indistinguishable against the background ofthe ti passageway then visible through the transparent plate 17.However, when a ball Si) occupies a space underlying a numeral, thenumeral is perceptibly more prominent.

In the application of the calculator 10 to resolve various arithmeticalproblems, including the operation of addition, subtraction,multiplication and division, the base 11 is tilted and the gate means 31positioned to open the passageway so as to cause all of the balls liketo roll into the upper portion 35 of the passageway 18. The gate means31 is then released to close the passageway 18 and the base 11 is tiltedinto an angular position approximating that of FIG. 1l or into avertical position by either manually manipulating the handle 14 orsupporting the base on the means 26. The balls Si) residing in the upperportion are now biased to roll downwardly and are blocked by the gatemeans 31.

Assume that the number 3 is to be added to the number 2 in an additionproblem. The forked end 93 of the stop member 91 is inserted into theslot 94 between the spaces marked 3 and 4 so as to captivate the rstthree balls adjacent to the gate means 32. The actuator 47 is thenpressed downwardly to position the stop member 32 into the position 32of FIG. 3 so as to open the passageway 13. The balls 39 positioned underthe spaces marked l, 2 and 3 are now free to roll downwardly in thepassageway to the blind end 22 where the three balls then underlie thenumerals 1, 2 and 3 of the indicia 98. The actuator member 47 is thenreleased for closure of the passageway 18 by the gate member 32 and thesto-p member 911 is removed so as to allow the remaining balls to rolldownwardly until the ball that had been positioned under the spacemarked 4 is positioned under the space marked 1 and abutting the gatemember 32. The stop member 91 is then inserted into the slot between thespaces marked by the numerals 2 and 3 whereby the balls occupying thespaces marked 1 and 2 are captivated between the forked member 93 andthe gate member 32 and the ball occupying the space marked 3 is blocked.The actuating member 47 is again actuated to retract the gate member 32and the balls occupying the spaces l and 2 are freed to roll downwardlyin the passageway 18 and till the spaces 4 .and 5 adjacent to the iirstthree balls previously released. In this manner, the last ball to bereleased occupies the space marked 5 and by color contrast makes thenumeral 5 more prominently visible, indicating the result. The highestnumber to be made prominently visible indicates the result. Additionalnumbers may be added by releasing an additional predetermined amount ofballs in like manner and the result indicated by the last released ball-occupying the lower portion 9i) of the passageway 18.

As an example of the operation ot subtraction, assume that three (3) isto be subtracted from ten (l0). Two methods may be employed to achievethe result. In the first method, lthe passageway 18 is blocked by a stopmember 91, by insertion of its forked end 93 in the slot 94 between thespaces marked by the numerals ten (10) and eleven (11). This blocks theball 80 occupying the space indicated by eleven (11) from rollingdownwardly. Next, another stop member like 91 is positioned in the slotbetween the spaces marked three (3) and four (4) to indicate the numberto be subtracted. The gate member 32 is then retracted 4from thepassageway 18 by the actuator 47 to release the balls occupy-ing thespaces one (l), two (2) and three (3) to roll downwardly into the lowerportion of the passageway 18. The `actuator 47 is then released toreturn the gate member 32 to its blocking position and the second stopmember like 91, the one position between Ithe spaces three (3) and four(4) is removed to allow the balls remaining between the two s-top meansto roll downwardly into abutment with the gate member 32 indicating theresult to be seven (7).

In the second of the subtraction methods, a stop member 91 is positionedto block lthe balls above the tenth ball and a second stop member 91 ispositioned by counting three spaces downwardly, relative to the slope ofthe passageway 18, .and away from the stop member blocking the eleventhball, whereby, upon retraction of the gate member 32, the seven ballsresiding in the spaces between the second stop member and the gatemember 32 are free to roll downwardly in the lower portion 9i) to residein the iirst seven spaces adjacent `to the end 22 and indicate a resultof seven (7).

For multiplication, as for example, three (3) times nine (9), one of thestop members 91 is inserted into the slot above `the ninth space in theupper portion of the passageway and the gate Vmeans 32 is retracted byactuation of the actuator member 39 in la lateral direction aspreviously described. The nine balls are then released to rolldownwardly into the lower portion 90 of `the passageway 18 to occupy`the first nine spaces adjacent lto the blind end 22. The actuator 39 is`then released to block the passageway 18 and lthe stop member 91withdrawn for a time interval sufficient to allow `the remaining ballsin the upper portion 96 to roll downwardly to abut a ball against thegate member 32 and refill the first nine spaces. The stop member 91 isthen reinserted in the same slot and the gate member retracted again byactuating the actuator member 39 to again release another nine balls toback up the first nine balls adjacent to the end 22 and thereby indicatethe numeralf eighteen (18) as the total. A third repetition of `thisoperation :to release nine more balls nally positions Kthe last releasedbml under the numeral in the space marked 27 to indicate a totaltwenty-seven (27). Each actuation of the actuator 37 has meanwhilerotated the disc 61 and the numeral three (3) appears in the window 64to indicate the multiplier.

In the operation of division, assume the example as nine (9) divided bythree (3). This is accomplished by placing a stop member 91 in the sletabove the space numbered nine (9) in the upper half 85 of the passageway18, thereby captivating nine balls in the accumulated space above thegate means 32. Another stop member like 91 is then inserted in the slotabove the space three (3) and the gate means is retracted by actuationof the actuator 39 to release the balls into the lower portion 9i) ofthe passageway 18. When the actuator 39 is released, the number one (l)on the disc 61 is registered with the opening 64. The gate member 91indicating the divisor of three (3) is then removed to allow theremaining balls below the stop member blocking above the space nine (9)to roll downwardly into abutment with lthe gate member 32. The secondstop member 91 is reinserted above the space three 3) and the threeballs captivated between the second stop member and the gate member 32are released upon subsequent actuation of the actuator 39 to rolldownwardly into the lower portion 90. Actuation of the `actuator member39 is repeated as long as there are balls remaining in quantity equal toor greater' than the divisor of three (3) for dividing, the result beingregistered by numerals registrable with the window 64. In the event thata number which is unequally divisable is used, the remainder isindicated in `the number of balls remaining above the gate member 32,whereas the result `is shown by the window 64.

For convenience, stop members like 91 are preferably stored in slots 94,extending through the wall 12 adjacent to the area occupied by thepassageway 13. To indicate the number of stop members like 91 to be usedin each operation, discrete stop members are provided for each operationsuch as one for the operation oi' addition, two for the operation ofsubtraction, one for the operation of multiplication and two fordivision. Instructions are also preferably printed or otherwiseinscribed adjacent to the stop member pro-vided therefor.

Additional space of the wall 12 may be utilized for the provision of acompartment indicated by the numeral 99 having a hinged cover indicatedby the numeral 1li@ for storage of pencils, pens, or the like.

While the instant invention has been shown and described herein in whatis conceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom in the scope of theinvention, which is therefore not lto be limited to the detailsdisclosed herein, but is to be `afforded the full scope of the claims.

What is claimed as new and desired to secure by Letters Patent is:

1. A calculator comprising: a base; means deiining a sinuous passagewayin said base and having blind ends, said base being tiitable into aplane wherein all portions of said passageway are downwardly sloped;manually operable gate means movably mounted in said base forselectively intersecting Isaid passageway so as to selectively open `andclose said passageway; a plurality of equally dimensioned rollablemembers residing in an upper portion of said passageway and arranged insingle tile therein, said rollable members being gravitationally biasedtowards said gate means in response to tilting of said basc into saidplane; and removable stop means selectively positionable in saidpassageway in upwardly spaced relationship to said gate means andspaceable in increments of said dimension of said rollable members forarresting movement of a selective rollable member residing in said upperportion of said passageway, whereby rollable members positioned betweensaid gate means and said stop means are gravitationally biased to rolldownwardly in said passage and toward the lowermost of said blind endsin response to actuation of said gate means to open said passageway,said calculator also including indicator means in said base andselectively operable in response to actuation of said gate means forindicating the number of actuations of said gate means.

2. A calculator comprising: a base; means defining a sinuous passagewayin said base 'and having blind ends, said passageway being comprised ofa groove in said base and a transparent panel overlying said groove soas to enclose said groove, said base being tiltable into a plane whereinall portions of said passageway are downwardly sloped; manually operablegate means movably mounted in said base for selectively intersectingsaid passageway so as to selectively open and close said passageway; aplurality of equally dimensioned rollable members residing in an upperportion of `said passageway and arranged in single le therein, saidrollable members being gravitationally biased towards said gate means inresponse to tilting of said base into said plane; and removable stopmeans selectively positionable in said passageway in upwardly spacedrelationship to said gate means and spaceable in increments of saiddimension of said rollable members for arresting movement of a selectiverollable member residing in 'said upper portion of said passageway,whereby rollable members positioned between said gate means and saidstop means are gravitationally biased to roll downwardly in said passageland toward the lowermost of said blind ends in response to :actuationof said gate means to open said passageway, said calculator includingindicia means fixed on said `transparent panel and overlying the upperportion `of sa-id passageway above said gate means, said indicia meansbeing spaced in increments of said dimension of said rollable membersand prominently visible in response to occupation of rollable membersthereunder for numerically indicating the number of roller membersbacked up above said gate means, said passageway in said indicia meansbeing indistinguishable in color so as to make said indicia meanssubstantally invisible in the absence of a rollable member thereunder.

3. A calculator as defined in claim 2, including a sccond indicia meansxed on said transparent panel and overlying the lower portion of saidpassageway, below said gate means, said second indicia means beingspaced in increments of said dimension of said roller members,progressively from said lowermost of said blind ends of said passagewayand prominently visible in response to occupation of roller membersthereunder and released by said gate means for indicating the number ofroller members released by said gate means, said passageway and saidsecon-d indicia means being indistinguishable in color so `as to makesaid second indicia means substantially invisible in the absence of arollable member thereunder.

4. A calculator comprising: la base having a relatively flat face; meansdening a sinuous passageway in said face, said passageway having a pairof closed ends and -a plurality of rectilinear portions in angularrelationship to each other and curved portions connecting saidrectilinearportions; means for supporting said base in a plane Wherebyall portions of said passageway `are sloped downwardly from a horizontalplane; manually operable gate means movably mounted `on said base forselectively intersecting said passageway midway of its length so as toselectively open and close said passageway; a plurality of sphericalmembers of equal size residing in an upper portion of said passagewayabove said gate means and arranged in single stile in said passageway,said spherical members being gravitationally biased towards said gatemeans in response to tilting of said base into said plane; and removablestop means selectively positionable in said upper portion of saidpassageway and in spaced relationship to said gate means, said stopmeans being spaceable in increments of said spherical members forarresting movement of selective spherical members residing in said upperportion of said passageway; spherical members positioned between saidgate means in its closed position and said stop member beinggnavitationally biased to roll downwardly in said passageway and towardsthe lowermost of said blind ends in response to actuation of said gatemeans to open said passageway, said gate means including: slide meansjuxtaposed to said passageway 'for lateral movement relative to saidpassageway; a gate member movably mounted on said slide means andpositionable for closing and opening said passageway; first spring meansbiasing said slide means in a direction to bias said gate member into aposition closing said passageway; a first manually operable means foractuating said slide means so as to position said gate means to opensaid passageway; second spring means biasing said gate memberindependently of said rst spring means and into said position forclosing said passageway; and second manually operable means forselectively independently actuating said `gate member so as to positionsaid gate member to open said passageway.

5. A calculator as dened in claim 4, including indicating means operablein response to actuation of said -frst manually operable means forindicating the number of actuations of said gate means.

References Cited in the ile of this patent UNlTED STATES PATENTS 264,572Schwenniger Sept. 19, 1882 569,348 Phillips Oct. 13, 1896 982,901Thompson Jan. 31, 1911 1,508,212 Steinau July 29, 1924 2,253,563Humphreys Aug. 26, 1941 2,463,763 Grafi Mar. 8, 1949 2,800,728 BergmanJuly 30, 1957 FOREIGN PATENTS 827,878 Germany Ian. 14, 1952

1. A CALCULATOR COMPRISING: A BASE; MEANS DEFINING A SINUOUS PASSAGEWAYIN SAID BASE AND HAVING BLIND ENDS, SAID BASE BEING TITABLE INTO A PLANEWHEREIN ALL PORTIONS OF SAID PASSAGEWAY ARE DOWNWARDLY SLOPED; MANUALLYOPERABLE GATE MEANS MOVABLY MOUNTED IN SAID BASE FOR SELECTIVELYINTERSECTING SAID PASSAGEWAY SO AS TO SELECTIVELY OPEN AND CLOSE SAIDPASSAGEWAY; A PLURALITY OF EQUALLY DIMENSIONED ROLLABLE MEMBERS RESIDINGIN AN UPPER PORTION OF SAID PASSAGEWAY AND ARRANGED IN SINGLE FILETHEREIN, SAID ROLLABLE MEMBERS BEING GRAVITATIONALLY BIASED TOWARDS SAIDGATE MEANS IN RESPONSE TO TILTING OF SAID BASE INTO SAID PLANE; ANDREMOVABLE STOP MEANS SELECTIVELY POSITIONABLE IN SAID PASSAGEWAY INUPWARDLY SPACED RELATIONSHIP TO SAID GATE MEANS AND SPACEABLE ININCREMENTS OF SAID DIMENSION OF SAID ROLLABLE MEMBERS FOR ARRESTINGMOVEMENT OF A SELECTIVE ROLLABLE MEMBER RESIDING IN SAID UPPER PORTIONOF SAID PASSAGEWAY, WHEREBY ROLLABLE MEMBERS POSITIONED BETWEEN SAIDGATE MEANS AND SAID STOP MEANS ARE GRAVITATIONALLY BIASED TO ROLLDOWNWARDLY IN SAID PASSAGE AND TOWARD THE LOWERMOST OF SAID BLIND ENDSIN RESPONSE TO ACTUATION OF SAID GATE MEANS TO OPEN SAID PASSAGEWAY,SAID CALCULATOR ALSO INCLUDING INDICATOR MEANS IN SAID BASE ANDSELECTIVELY OPERABLE IN RESPONSE TO ACTUATION OF SAID GATE MEANS FORINDICATING THE NUMBER OF ACTUATIONS OF SAID GATE MEANS.